Protecting Public Health and the Environment.

Owyhee River (Upper) Subbasin

Subbasin at a Glance

Hydrologic Unit Code 17050104
Size 2,163 square miles (1,384,288 acres) total
1,582 square miles (1,012,411 acres) in Idaho

Water Bodies with EPA-Approved TMDLs (Category 4a)

Battle Creek, Beaver Creek, Blue Creek, Blue Creek Reservoir, Camas Creek, Camel Creek, Castle Creek, Deep Creek, Juniper Basin Reservoir, Nickel Creek and tributaries, Pole Creek, Red Canyon Creek, Smith Creek, Thomas Creek

Beneficial Uses Affected Cold water aquatic life, salmonid spawning, primary and secondary contact recreation
Major Land Uses Rangeland, riparian, forestry, irrigated agriculture
Date Approved by EPA March 2003
Approval Letter
Date Addendum Approved by EPA July 2012
Approval Letter

Subbasin Characteristics

The Upper Owyhee River subbasin encompasses a large area in southwest Idaho. The headwaters for the Owyhee River (East Fork) originate in northeast Nevada in the Independence Mountains.

2003 Subbasin Assessment and TMDL

Through the Upper Owyhee River subbasin assessment process, it was determined that most streams in the subbasin on Idaho’s 1998 §303(d) list have cold water aquatic life and salmonid spawning as existing uses. In some cases, data show these uses are not supported due to exceedances of the Idaho water quality standards temperature criteria. In other cases, biological information showed impairment to cold water aquatic life and salmonid spawning.

Two streams were listed as not supporting primary and secondary contact recreation due to the presence of bacteria. However, monitoring has indicated those streams are in full support of the recreation beneficial uses.

A TMDL has been developed for each stream determined to be not fully supporting beneficial uses in accordance with Idaho water quality standards. The TMDLs address temperature reductions required to meet Idaho water quality standard criteria and/or instream sediment goals to maintain or restore cold water aquatic life and salmonid spawning. The TMDLs use management objectives dealing with riparian conditions to obtain these goals.

2003 TMDL: Streams and Pollutants for Which TMDLs Were Developed

Deep Creek
Sediment, temperature
Pole Creek
Temperature
Castle Creek
Sediment, temperature
Red Canyon Creek
Temperature
Nickel Creek
Sediment
Blue Creek Reservoir
Sediment
Juniper Basin Reservoir
Sediment

2012 Addendum

This document addresses the temperature impairments of 36 assessment units in the Owyhee River watershed in southwest Idaho. The Owyhee River watershed incorporates the Upper, South, and Middle Fork Owyhee River subbasins.

Temperature TMDLs were previously written for many assessment units in the Owyhee River watershed. However, the Idaho Department of Environmental Quality (DEQ) recommended rewriting those TMDLs using more appropriate shade targets based on knowledge of local vegetation types and natural stream widths. This document revises 25 previous TMDLs and establishes 11 new TMDLs.

 Subbasin  Hydrologic Unit Code (HUC)  Assessment Units with New TMDLs  Assessment Units with Updated TMDLs
Upper Owyhee River  17050104  11  10
South Fork Owyhee River  17050105  0  2
North and Middle Fork Owyhee River  17050107  0  13

2012 Addendum: Assessment Units and Pollutants for Which TMDLs Were Developed

Upper Owyhee River Subbasin

Description Assessment Unit Pollutant
Battle Creek upstream of Antelope Flat ID17050104SW023_02 Temperature
Battle Creek between Antelope Flat and Big Springs Creek ID17050104SW023_03 Temperature
Battle Creek between Big Springs Creek and Owyhee River ID17050104SW023_04 Temperature
Deep Creek between Hurry Back and Nickel Creeks ID17050104SW026_04 Temperature (updated)
Deep Creek between Nickel Creek and Owyhee River ID17050104SW026_05 Temperature (updated)
Pole Creek upstream of Mud Flat ID17050104SW028_02 Temperature (updated)
Pole Creek between Camas Creek and Mud Flat ID17050104SW028_03 Temperature (updated)
Pole Creek between Camas and Deep Creeks ID17050104SW028_04 Temperature (updated)
Camas Creek between Big Springs Butte and Pole Creek ID17050104SW029_03 Temperature
Camel Creek upstream of Sunshine Valley Creek ID17050104SW030_02 Temperature
Nickel, Smith, and Thomas Creek headwaters ID17050104SW031_02 Temperature
Nickel, Smith and Thomas Creeks—3rd order ID17050104SW031_03 Temperature
Nickel and Smith Creeks—4th order ID17050104SW031_04 Temperature
Castle Creek upstream of Skunk Creek ID17050104SW032_02 Temperature (updated)
Castle Creek between Skunk and Deep Creeks ID17050104SW032_03 Temperature (updated)
Beaver Creek upstream of Carter Creek ID17050104SW033_02 Temperature
Beaver Creek between Carter and Trap Creeks ID17050104SW033_03 Temperature
Beaver Creek between Trap and Deep Creeks ID17050104SW033_04 Temperature
West Fork Red Canyon ID17050104SW034_02 Temperature (updated)
East Fork Red Canyon and Red Canyon upstream of Petes Creek ID17050104SW034_03 Temperature (updated)
Red Canyon between Petes Creek and Owyhee River ID17050104SW034_04 Temperature (updated)

 

South Fork Owyhee River Subbasin

Description Assessment Unit Pollutant
South Fork Owyhee River upstream of Little Owyhee River ID17050105SW001_06 Temperature (updated)
South Fork Owyhee River downstream of Little Owyhee River ID17050105SW001_07 Temperature (updated)

 

North and Middle Fork Owyhee River Subbasin

Description Assessment Unit Pollutant
Middle Fork Owyhee River upstream of Summit Springs Creek  ID17050107SW004_02 Temperature (updated)
Middle Fork Owyhee River downstream of Summit Springs Creek ID17050107SW004_03 Temperature (updated)
North Fork Owyhee River upstream of Big Springs Creek ID17050107SW008_02 Temperature (updated)
North Fork Owyhee River between Big Spring and Pleasant Valley Creeks ID17050107SW008_03 Temperature (updated)

North Fork Owyhee River between Pleasant Valley and Juniper Creeks, and

Juniper Creek between Cabin Creek and North Fork Owyhee River
ID17050107SW008_04 Temperature (updated)
North Fork Owyhee River downstream of Juniper Creek ID17050107SW008_05 Temperature (updated)
Pleasant Valley Creek upstream of East Fork Pleasant Valley Creek ID17050107SW009_02 Temperature (updated)
Pleasant Valley Creek between North Fork Owyhee River and East Fork Pleasant Valley Creek ID17050107SW009_03 Temperature (updated)
Noon Creek ID17050107SW010_02 Temperature (updated)
Cabin and Corral Creek headwaters ID17050107SW011_02 Temperature (updated)
Cabin and Corral Creeks—3rd order ID17050107SW011_03 Temperature (updated)
Juniper Creek upstream of Buck Creek ID17050107SW012_02 Temperature (updated)
Juniper Creek between Buck and Cabin Creeks ID17050107SW012_03 Temperature (updated)

Subbasin Documents


Staff Contacts

Senior Water Quality Analyst
Julia Achabal
DEQ Boise Regional Office
1445 N. Orchard St.
Boise, ID 83706
(208) 373-0550
julia.achabal@deq.idaho.gov